Taxonomic and ecological relevance of the chlorophyll a fluorescence signature of tree species in mixed European forests

Abstract

The variability of chlorophyll a fluorescence (ChlF) parameters of forest tree species was investigated in 209 stands belonging to six European forests, from Mediterranean to boreal regions. The modifying role of environmental factors, forest structure and tree diversity (species richness and composition) on ChlF signature was analysed. At the European level, conifers showed higher potential performance than broadleaf species. Forests in central Europe performed better than those in Mediterranean and boreal regions. At the site level, homogeneous clusters of tree species were identified by means of a principal component analysis (PCA) of ChlF parameters. The discrimination of the clusters of species was influenced by their taxonomic position and ecological characteristics. The species richness influenced the tree ChlF properties in different ways depending on tree species and site. Tree species and site also affected the relationships between ChlF parameters and other plant functional traits (specific leaf area, leaf nitrogen content, light-saturated photosynthesis, wood density, leaf carbon isotope composition). The assessment of the photosynthetic properties of tree species, by means of ChlF parameters, in relation to their functional traits, is a relevant issue for studies in forest ecology. The connections of data from field surveys with remotely assessed parameters must be carefully explored.

Long‐term measurements of chlorophyll a fluorescence using the JIP‐test show that combined abiotic stresses influence the photosynthetic performance of the perennial ryegrass (Lolium perenne) in a managed temperate grassland

“…Rapid reduction of the end electron acceptor is typical of ‘sun leaves’ and expresses a high PSI/PSII ratio (Cascio et al ). Similar photosynthetic behavior was observed among southern European tree species, which exhibited a higher electron transport beyond PSI, as well as lower F V /F M and PI ABS values than species from more northern regions (Pollastrini et al , ). This behavior was interpreted as acclimatization to higher solar radiation for these species and suggests a rapid delivery of electrons to the final acceptors and then on to the Calvin cycle (photochemical de‐excitation).…”

Tree species diversity affects decomposition through modified micro‐environmental conditions across European forests

“…As an index of water availability per degree of temperature, which may be particularly informative for the decomposition process, we computed an additional climatic index by dividing the cumulated precipitation over the entire incubation period by the summed daily mean temperature. Canopy density was estimated using the plot-specific leaf area index (LAI; m 2 m À2 ) (see Pollastrini et al, 2016). As indicators of soil properties, we used the carbon : nitrogen (C : N) ratio and pH of the upper mineral soil layer (below the forest floor layer), at 0-10 cm.…”

A User’s View of the Parameters Derived from the Induction Curves of Maximal Chlorophyll a Fluorescence: Perspectives for Analyzing Stress

“…The JIP-test is capable not only to assess different kind of stresses but also to distinguish between specific responses for a given type of stress, due, for instance, to genotypic differences, to differences in stress intensity, or to differences in the developmental stage of plants at the time stress is applied. JIP parameters were found to be capable to distinguish among tree species (Pollastrini et al, 2016). The above-mentioned parameters, J 0 DI /J ABS , V K /V J and J 0 RE1 /J ABS , were found to be relevant parameters to evaluate responses to WD as a function of genotype diversity for a given plant species, in barley (Oukarroum et al, 2007, 2009) and in tomato ( Table 1 ).…”